I'm Lucy, and I'd be happy to answer your questions today.
If you signed a contract stating that they promised to sell you a car for a specific price and a specific monthly payment, that is binding on them. But not giving you that payment, they're in breach of contract. You do not have any legal obligation whatsoever to agree to a higher payment. Look at your contract very carefully - sometimes it says something like the contract is contingent upon you receiving financing. If that's the case, and they couldn't get the promise payments, the contract fails. You have no agreement, and they'd have to give your car back and cancel the deal. But the contract may also require that you make reasonable efforts to find financing, which could mean applying for loans at other banks. Go through the paperwork you signed.
And if they try to make you sign anything other than the original agreement, you can insist that they show you WHERE the original contract says you have to. Otherwise, they can't make you pay more. And it could be a violation of unfair and deceptive trade practices laws to promise someone an interest rate or payment that is not available, so if they give you a hard time, you can ask the Attorney General's Office to investigate (and you can tell them you're doing that).
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